Component 4: Introduction to Information and Computer Science Unit 4: Application and System Software Lecture 2 This material was developed by Oregon Health & Science University, funded by the Department of Health and Human Services, Office of the National Coordinator for Health Information Technology under Award Number IU24OC000015. Unit 4 Objectives a. Define application vs. system software. b. Give examples of application software and the elements that comprise them, focusing on healthcare systems. c. Describe the functions of system software (OS), including file organization (file types, downloading, zipped files). d. List different types/brands of Operating Systems. e. Explain the purpose and usage of file systems. Component 4/Unit 4-2 Health IT Workforce Curriculum 2 Version 2.0/Spring 2011 System Software • Consists of programs that control/maintain operations of computer • Two types – Operating Systems – Utility Programs Component 4/Unit 4-2 Health IT Workforce Curriculum 3 Version 2.0/Spring 2011 1 Operating System (OS) • A set of programs that coordinate all activities of hardware resources • It’s the layer between the hardware and application software • It’s unique to each individual computer hardware system Component 4/Unit 4-2 Health IT Workforce Curriculum 4 Version 2.0/Spring 2011 Example Suppose you want to print a document from a word processor • Start the word processor – You click on the icon for the word processor – The OS starts the program • Open the document – You select the document to open – The word processor requests that the OS find the document on the hard disk – The OS finds it and sends it back to the word processor – The word processor displays the document • Print the document – You select print – The word processor tells the OS to print the document – The OS sends the document to the printer – The printer prints it Component 4/Unit 4-2 Health IT Workforce Curriculum 5 Version 2.0/Spring 2011 Functions of an OS • Interfacing with users • Booting the computer • Configuring devices • Managing processes • Managing resources • Managing memory • Managing files • Providing security Component 4/Unit 4-2 Health IT Workforce Curriculum 6 Version 2.0/Spring 2011 2 Interfacing with Users • Command line • GUI • Examples • Examples – DOS – Microsoft Windows – Unix – Mac OS and Mac OS X – Linux (without windowing) – KDE (Linux windowing) Note: we will describe the different operating systems in detail later in the lecture. Component 4/Unit 4-2 Health IT Workforce Curriculum 7 Version 2.0/Spring 2011 Booting the Computer • First task when you turn on computer • Starts the BIOS (Basic Input/Output System) stored in ROM • The BIOS starts the OS – The “kernel” is started and runs the entire time your computer is powered on – Other utility programs are started later as needed – Detects devices and ensures they are configured properly • Other applications are launched – Determined by startup scripts Component 4/Unit 4-2 Health IT Workforce Curriculum 8 Version 2.0/Spring 2011 Configuring Devices • Devices are components that are connected to the computer – Printer, scanner, etc. • OS configures devices – Device drivers are small programs used by the OS to communicate with the device – The are unique to the OS (and version) and hardware – Need new device drivers when • Device driver is corrupted or overwritten • Upgrade computer • Upgrade device • Upgrade OS Component 4/Unit 4-2 Health IT Workforce Curriculum 9 Version 2.0/Spring 2011 3 Managing Processes • Processes are programs that are running • Most PCs have operating systems that are single user/multitasking – One user – Multiple programs/processes running at once • The OS has to manage which process is active (foreground process) and which are not (background processes) Component 4/Unit 4-2 Health IT Workforce Curriculum 10 Version 2.0/Spring 2011 Managing Resources • There are many resources in a computer – CPU – Memory – Devices – Disk storage – Network • The operating system controls which process controls which resource • It implements a scheduler for the processes so that each process gets a share of CPU time – Gives the illusion that multiple programs are running at the same time • It controls how devices are shared among processes • It provides access to memory, disk storage and the network Component 4/Unit 4-2 Health IT Workforce Curriculum 11 Version 2.0/Spring 2011 Processes View • Every OS provides a way to view running processes and the resources they use – Microsoft Windows has Task Manager – Mac OS has Activity Monitor/Process Viewer – “top” command in Unix/Linux Component 4/Unit 4-2 Health IT Workforce Curriculum 12 Version 2.0/Spring 2011 4 Managing Memory • The OS manages memory – How it’s accessed/addressed – Retrieving/storing data from/into memory • Modern OS use virtual memory to give the illusion of more memory – Virtual memory larger than physical memory – OS maps virtual memory to physical memory – Uses hard disk space (“swap space”) for the part of virtual memory not currently loaded into physical memory (RAM) – “Swapping” is when instructions/data in “swap space” are loaded into RAM and some other instructions/data previously in RAM are saved in the “swap space” Component 4/Unit 4-2 Health IT Workforce Curriculum 13 Version 2.0/Spring 2011 Managing Files • Files are all the documents on your computer – Are organized into folders/directories • The OS controls how these files are stored in secondary storage (hard disk drive) by using a file system • The file system provides an interface to the user for viewing and manipulating files – View file lists and folders/directories – Provides functions like copy, rename, move, delete, etc. • The file system provides access to files/folders for application software Component 4/Unit 4-2 Health IT Workforce Curriculum 14 Version 2.0/Spring 2011 Providing Security • The Operating System provides some security – All processes related to OS run in system mode – Users can be defined as having different levels of access to the computer – Can be configured to update automatically – Can include integrated firewall • Still need standalone security applications – Anti-viral, anti-spyware, anti-malware Component 4/Unit 4-2 Health IT Workforce Curriculum 15 Version 2.0/Spring 2011 5 Utility Programs • Software that performs a system maintenance task – Backing up files, diagnosing system problems, searching for a file, compressing files, etc. – Can provide accessibility features • Can be included in OS or added as a stand-alone program Component 4/Unit 4-2 Health IT Workforce Curriculum 16 Version 2.0/Spring 2011 Types of OS • For personal computers • For servers • For hand-held devices • For embedded computers Component 4/Unit 4-2 Health IT Workforce Curriculum 17 Version 2.0/Spring 2011 OS for PCs • DOS • Microsoft Windows – Microsoft Windows 1.0 through 2000 – Windows NT – Microsoft Windows XP – Microsoft Windows Vista – Microsoft Windows 7 • Mac OS – Classic Mac OS – Mac OS 9 – Mac OS X 10.1 – 10.4 – Mac OS X 10.4.4 (Tiger Intel) – Mac OS X 10.5 (Leopard) – Mac OS X 10.6 (Snow Leopard) Component 4/Unit 4-2 Health IT Workforce Curriculum 18 Version 2.0/Spring 2011 6 Microsoft Windows XP Component 4/Unit 4-2 Health IT Workforce Curriculum 19 Version 2.0/Spring 2011 Mac OS X 10.6 Component 4/Unit 4-2 Health IT Workforce Curriculum 20 Version 2.0/Spring 2011 Windows vs. Mac OS X • Strengths of Windows: • Strengths of Mac OS X: – Most applications – Easy to use available for Windows – Reliable – Large variety of – Secure hardware that run • Weaknesses of Mac OS X: Windows – Limited software – Great support for availability devices • Weaknesses of Windows: – Reliability – Security Component 4/Unit 4-2 Health IT Workforce Curriculum 21 Version 2.0/Spring 2011 7 OS for PCs and Servers • Unix – Developed in 1969 – Used for mainframes – Many different variations available • Linux – Open source version of Unix created by Linus Torvalds in 1991 Component 4/Unit 4-2 Health IT Workforce Curriculum 22 Version 2.0/Spring 2011 Linux (KDE 4 Windowing Environment) Component 4/Unit 4-2 Health IT Workforce Curriculum 23 Version 2.0/Spring 2011 Unix Component 4/Unit 4-2 Health IT Workforce Curriculum 24 Version 2.0/Spring 2011 8 OS for Servers • Mac OS X Server • Microsoft Windows Server – Versions 2000, 2003, 2008, 2008 R2 – Windows HPC Server 2008 • Windows Small Business Server • Windows Essential Small Business Server • Windows Home Server • Unix/Linux Component 4/Unit 4-2 Health IT Workforce Curriculum 25 Version 2.0/Spring 2011 OS for Handheld Devices • Palm OS • Microsoft Windows Mobile OS/Phone 7 • iPhone iOS 4 • Blackberry OS • Android OS Android OS Component 4/Unit 4-2 Health IT Workforce Curriculum 26 Version 2.0/Spring 2011 OS for Embedded Systems • Embedded systems need their own OS • Some are proprietary and developed for that system alone • Some are commercially available and customizable – “Windows XP for Embedded Systems” version of XP (known as XPe) is made up of components – An implementation of XPe installs only the components of the OS that are necessary • Decreases the size of the OS • Increases the OS’s security • XPe was superseded by Windows Embedded Standard 2009, the current version • XPe is not available for PCs as it is licensed to original equipment manufacturers (OEMs) who develop the embedded systems Component 4/Unit 4-2 Health IT Workforce Curriculum 27 Version 2.0/Spring 2011 9 Embedded OS Example • The SonoSite, Inc. hand-carried ultrasound device runs with Windows Embedded CE – Is handheld – Easy to use – Boots in less than 15 seconds – Provides instant images at an accident site or hospital setting – Allows for USB support Microsoft Web site, SonoSite Inc. M-Turbo Portable Ultrasound: Embedded medical Devices, Online: http://www.microsoft.com/windowsembedded/en- us/about/casestudies/m-turbo.mspx , 2010.